ass Solution {
public:
    string kthDistinct(vector<string>& arr, int k) {
        map<string,int> mp;
        //统计出现次数
        for(auto &str:arr)
        {
            mp[str]++;
        }
        for(auto &str:arr)
        {
            if(mp.find(str)->second==1)
            {
                k--;
                if(k==0)
                return str;
            }
        }
        return "";
    }
};
